Close coupling device for tractor-trailers



June 8 1954 J. J. JOHNSON ETAL 2,680,627

CLOS COUPLING DEVICE FOR TRACTORrTRAILERS Filed March 15, 1950 ,iZZoz-Weys.

Patented June 8, 1954 UNITED YSTATES TENTv OFFICE CLOSE VGO'lJ'ILIlM DEVICE FOR TRACT Clt-TRAILERS J ohnJ Johnson andMilford W. Lempke, Buffalo,

and Alfred J. Gentile, Cheektowaga, N. Y., assignors to Delavan Welding Company, Inc., Burial@ N. Y., a corporation of New York Application March 15, 1950, Serial No. 149,826

Claims. (Cl. 28o-438) Of-the king pin, this :axis being substantially fixedA relative to the truck frame.- If the semi-trailer has aportion of its bodyladjacent the-rear end oi and semi-trailer to jack-knife and thereby imthe truck extending below the horizontal plane proves the safety ofthe unit on the highways. of the fifth wheel meinberas in a vehicle carry- Another object is to provide such a coupling ing or convoy type trailer, the anglel through device which is strong, dependable and not likely which the truck. can turn relative tothe trailer to get out of order or require repairs. is usually limited by the rear wheels oi the truck u A'further object is to provide such a couplingr striking the trailer body. This angle in practice device which is simple in construction and inis substantially less than 90 degrees. At first expensive to manufacture, and further of such blush,fit could be saidthat this interference bea nature that existing trailers can be readily tween the truck wheels and trailer Vbody could mod-ined to incorporate the same. be eliminated by further cutting back the depend- Still further objects and advantages of the ing .portion of the trailer body. However, tov do present invention will be apparent from the folso would decrease the load carrying capacity of lowing detailed description and accompanying the trailer since. the-load -carryingspace lost at drawing wherein: the front of the trailer by cutting it'back could Fig. 1 is a side elevational View of a` truck and not be made up at the rear end ofthe trailer. To semi-trailer embodying the present invention, the do this would necessitate increasing the over-all o semi-trailer illustrated being of the vehicle carrylength ci the truck-trailer unit and this may be ing or convoy type. impossible since the., maximum over-all length Fig. 2 is an enlarged fragmentary top plan view of truclvtrailer units is prescribed by highwayy of the front end of thesemi-trailer and rear end regulations. A similar problem. of interferenceY 3.. of the truck shown in' Fig. 1. exists in box-.type trailer bodies which strike the l Fig. 3 is a still further enlarged fragmentary cab of the truck` during extreme turning, this longitudinal sectional viewthereof taken on line problem having been solved by rounding the front 3 3, of Fig. 2. corners of the trailer body at ,the expense of re- Figs. 4 and 5 are views similar to Fig. 2 but on ducing the load carryingcapacity of the trailer. o a reduced scale and taken along the line A-A While coupling devices for connecting together of Fig. 3 and illustrating the relative positions of a truck and semi-trailer which permit of close parts of the coupling device during different turn coupling the truck and trailer during straight angles of the truck relative to the semi-trailer. ahead driving and yet .operate during turning to Fig, 6 is an exploded elevational perspective spread or separate the vehicles farther apart to view of the coupling device'embodying the presprovide increased turning clearance have been ent invention. devised .these devices have not proven .completely Fig. 7 is an enlarged fragmentary vertical satisfactory for one reason or another. transverse sectional view of thel coupling devicev it is accordingly .the principal object of the taken on line 'l-l, of Fig. 2. present invention to Vprovide van improved cou- The truck illustrated in the drawing is of conpling device-ior'connecting `together a .truck andV ventional construction and is shown as having a a semi-trailer which devicepermits the'truck and frame F including a pair of transversely spaced semi-trailer to be closely coupled during movelongitudinal channel shaped frame members nient in a direction along: the common center l--HL In accordance with conventional praclines ,of the vehicles andiwhich operates during. o5 tices a liith wheel member Mis showny as mounted relative turning between the truck and trailer' to spread or further separate these. vehicles thereby to provide `increased clearance and avoid interference therebetween.

Another object is to provide such a coupling device which permits the truck to be turned through a greater angle relative to the semitrailer, as much as if desired.

Another object is to provide such a coupling device which permits of quick coupling.y and uncoupling of the truck .and semi-trailer and this from any'angle of misalignment therebetween.

Another object is to provide such a coupling device which reduces the tendency of the truck on the frame members l0 near their rear ends so as to be oscilla-table or rockable about a horizontal axis extending transversely of the truck frame, this being accomplished by arranging the 'fth wheel member on a pivot rod ii the ends or which are journalled in bearing blocks l2l2 bolted to the truck frame members le.

The fth Wheel member M may be of any suitable conventional design, that shown having a slot or notch i3 extending longitudinally of the truck frame and leading from the rear transverse edge of the member to a point approximately above the pivot rod H. A pair of movable jaws iQ-Hl are carried by the fth wheel member M and are movable transversely thereof so as to embrace the rear side of the king pin on the semi-trailer and lock this pin in the bottom or at the forward closed end of the slot or notch i3. The jaws tbl form no essential part of the present invention and hence a detailed showing and description of their actuating means is not necessary.

The semi-trailer shown is represented by the reference character T and may be of any suitable construction. As shown the semi-trailer T at its front end has a deck plate l5 and a perimetrical channel shaped frame member le. The semitrailer shown has a main floor which is arranged considerably below the level of the deck plate l5 and the semi-trailer at its front end is cut out as indicated at i8 to provide clearance between the trailer and the rear wheels of the truck during turning. A conventional type landing gear i9 is shown for supporting the semi-trailer when uncoupled or disconnected from the truck.

The coupling device embodying the present invention is operatively interposed between the fth wheel member M and the front end of the semi-trailer T which overlaps the truck frame F. The coupling device is shown as comprising a bearing member' 2li of rectangular plate form arranged against the lower surface of the deck plate i5. This plate member carries an upstanding pivot pin 2l, an upstanding follower pin 22 and a depending king pin 23. are shown as fixedly connected as by welding to the plate member 'All and arranged in line with one another, the upstanding follower pin 22 being near the front transverse edge of the plate member, the upstanding pivot pin 2i being near f the rear transverse edge thereof, and the depending king pin being arranged intermediate the pins 2l and 22.

The plate member 2n is arranged for pivotal action relative to the semi-trailer T about the I.

axis of the pivot pin 2! while said axis is movable in a fore and aft direction along the center line or longitudinal axis of the semi-trailer. To this end, the pivot pin 2l works in a guideway extend ing longitudinally of the semi-trailer T and the follower pin 22 works in a guideway extending transversely of the semi-trailer T. As shown, the deck plate IL1 is provided with a longitudinal rectilinear slot 2a surrounded by upstanding side and end guide walls 2E, and also with a transverse slot 25 surrounded by upstanding side and end guide walls 28. While the guide walls 25 and 23 are shown as welded to the deck plate l5, if desired, the deck plate l5 with slots Eil and therein and the guide walls can be a casting so as to provide this structure as an integral member. Transverse members '3l can be arranged on the deck plate l5 to reinforce the same and also the side guide walls 25. The guide walls 25 and 28 are shown as set back slightly from the rhese three pins f.

edge of the respective slot 24 or 26 so as to leave a continuous inwardly projecting flange 2S for the slot 2F; and a similar flange 36 for the slot 26.

ln order to facilitate movement of the pins 2l and 22 in their respective slots 2t and 26, each of these pins is provided with a roller sleeve 3l adapted to engage the opposing side walls of the respective guideway. The lower ends of the roller sleeves 3l ride on the respective flanges 29 and 38 and their upper ends are level with the upper edges of the guide walls 25 and 28.

Each of the pins 2! and 22 is further shown as having its upper end reduced and threaded to receive a washer 32 and nut 33. The washers 32 engage and straddle the upper edges of the respective guide walls 25 and 28 and serve to support the plate member 2G on the deck plate l5 of the semi-trailer T. Thus when the truck and trailer are uncoupled or completely disconnected the plate member 2B being carried by the semitrailer, remains therewith.

When the truck and semi-trailer are operatively coupled together, the plate member 2e is prevented from rotating or shifting relative to the fifth wheel member M and is compelled to move therewith. The means shown for accomplishing this include a pair of transversely spaced guide bars 35 which closely embrace the opposite lateral sides of the iifth wheel member M adjacent the rear end thereof. These guide bars 35 being in rear of the king pin 23, there is provided a three point connection between the fifth wheel member M and the plate member 2B which prevents relative movement between these members so that when the truck turns relative to the semi-trailer the fifth wheel and plate members being locked together also turn with the truck frame. The front ends of the guide bars 35 nare forwardly and laterally outwardly as indicated at 36 to provide jointly a contracting guide track leading to the more closely spaced rear portions of the guide bars 35.

The transverse slot 26 can be rectilinear throughout its length or curved depending on the spreading action or turning clearance desired and as shown the intermediate portion of this transverse slot 25 is rectilinear and the extreme ends thereof curve rearwardly as indicated at 37.

The longitudinal and transverse guideways and the pin assemblies working therein can be covered, if desired, by box-like sheet metal covers (not shown).

Assuming the semi-trailer T standing on its landing gear I9, in order to couple the semitrailer with a truck the latter is backed up so that the upper surface of the fth wheel member M which will be in a downwardly and rearwardly tilted position engages the bottom surface of the plate member 2i] and slides thereunder. During this sliding the king pin 23 enters the slot or notch i3 and is guided by the side walls thereof as well as by the guide bars 35 toward the bottom of this notch, the rear end of the fth wheel member M tipping upwardly, after which the jaws lli are moved toward each other to lock the king pin to the fifth Wheel member M.

It will be seen that when the center lines of the truck and semi-trailer are in line as for straight ahead movement and as shown in Fig. 2, the follower pin 22 is at the center or midway of the ends of the transverse slot 26 and the pivot pin 2l is at the rear of the longitudinal slot 2d. Further, the pins 2i, 22 and 23 are in line with the common center lines of the truck and semi-trailer. Referring to Figs. 2 and 3,

sleeve 3l on thisiollower pin122 engaging the front side wall 28xof'thetransverse guideway.

When the truck .turns 'in either direction 'out of alignment with the semi-trailer. the. plate member l turns with the :.truck so ithat .the `line connecting the/centers of the'pins 2l :and i22rremains in line'with the'center "line ofthetruck,y and pivotal actionbetween .theV platernem'ber 20 and the trailer takes place about the axisof the forwardly moving pivot pin 2l. This forward movement of thepivot pin' 2l along the centerline of the semi-trailer T is effectedzby` the follower .pin 22 beingcaused'tomovelaterally along the transverse slot 26.` Since the center to center distance between the pins 2l and 22 is xed, both being mounted Jon the plate member 20, forward movementof the'pivoti'pin 2l along the slot 24 is'mandatory. It .will therefore be seenV that a longitudinal spreading 'of the truck and semi-trailer during turning' takes place.

Referring to Fig. 4 which represents in plan the truck turned to the left relative tothe semitrailer through an angle of aboutv Ll5 degrees, the follower pin is caused to move to` that side of the transverse slot 26' leading toward the center of the turn and to permit this the pivot pin 2i has moved forwardly along the .longitudinal slot 24.

Referring toFig. 5, the truck is shown as turned relative to the semi-trailer through an angle of. In this positionv the. follower about 75 degrees. pin 22 is shown at theextreme 'outer end of Ythe rearwardly curved end portion 3110i .the .slot26` and the pivot pin 2| is at about itsextreme forward position in the slot 24. Further turning'of the truck .relative to thev semi-trailer if desired.

could be permitted by extending V.the endsfof` the slot'ES rearwardly concentric aboutthe center of the pivot pin 2l in its extreme forward position. However, there would Vbe no further eiective spreading or further separatingof the truck and semi-trailer during such extreme additional turning.

It will also be seen that as the truck "turns back toward a straight ahead 'position the pinsv 2l and 22 will move from theA extreme position shown in Fig. 5, through the intermediate position lshown in Fig. 4 tc the normal position shown in Fig. 2. During thisy reverse turning or straightening out of the truck and 'semi-trailer,

the pin 2! moves toward the rear end of the',

longitudinal slot 24 thereby more clcsely'coupling the truck and semi-trailer.

While the present inventiondefines, for purposes of illustration, al compensating coupling that said one of said pins is connedto rectilinear movement in adirection extending parallel to the longitudinal centerline of 'said trailer, second guide means on said trailer operatively associated with the other of said 'pins anclso arranged that said other-offsaid pins isconnedr toalnovementinfa xlirectionzextending transverses ly' of saidLtraiIer, .at least the i' intermediate 'por- A tions of said.; transverse; movement being rectilinear, and means larrangedzto connect said movable member with va tractor sov that the` line. connecting. the Vcenters .of .said 4pins risin line withy and does notshiftfrelative to thelongitudinal.

centerline 'of said tractor, whereby during 'relativeV turningbetween saidt. tractor and trailer said movableL member has pivotal action Vrelative toisaid trailer .at all times about Vthe axisofsaid` one of said .pins `whilethe same moves alongits rectilinear path.

L2. Inv a semi-trailer, the. combination therewith of av coupling device comprising, a plate member `arranged below the front end VorsaidY trailer.andimovableztrelative thereto, a pairof spaced `upstanding pins. on. said plate` member, a guide on'saidtrailer arranged to conne movement of one' of saidpins'to rectilinear move-Y ment in adirecti'onextending longitudinally of said'trailer, a second guide on said trailer. arranged infront ofsaid rstY guide to coni-lne movement of the other ofv saidpins to movement in a direction 1 extendingy transversely of saidrtrailer, at Vleastthe intermediate portion of said transverse movement being. rectilinear, andv means arrangedto connectsaid platemember with a tractor so that'the'line Iconnecting `the centers of said' pins is -in line with and` does not shift relative to thecenterline of said tractor, lwhereby during relative turning between said tractor and trailer 'said .plate .member has pivotal action relative to said trailer atall times about the axis of said onefof said pins while the same moves along .its rectilinear path;

3. In a semi-trailer having a vdeck .plate atits front end, the combination therewith of a coupling device comprisinggaplate member movably arranged 'against the bottom `of said deck plate, a pair of spaced upstanding pins on said 'plate member and respectively projecting` through longitudinal and transverse groovesin said deck plate, guide walls extending along the sides of said longitudinal groove to guide the respective one of saidpin'sl for rectilinear movementextending longitudinallyof said trailer, guide walls extending alongr the sides of said transverse groove to guide the other of said pins for movement `extending transversely of said trailer, at least the .intermediate portion of Vsaidv transverse movement being rectilinear, roller means on said pins engaging `the'respective guide' walls, and

means arranged to connect said plate memberv with a tractor so that rthe line-connecting the centers of Vsaid pins is in line with and does-not shift relative to the longitudinal centerline of said tractor, whereby during relative turning between saidtractor and trailer said plate member'has pivotal action relativeto said trailer atY transverse grooves in'saiddeck plate, guidewalls extending along thel sides'ofV said longitudinal groove tofguideithe frespective one of .'saidnpins for: rectilinear" movement .extending longitudinally of saidfitraileni guide .walls.:extendingpalong:

the sides of said transverse groove to guide the other of said pins for movement extending transversely of said trailer, at least the intermediate portion of said transverse movement being rectilinear, roller means on said pins engaging the respective guide walls, a depending king pin on said plate member adapted to be locked to said fth wheel member of said tractor, and means on said plate member coopera-ble with said fifth wheel member to prevent relative rotation between said members about the axis of said king pin, whereby during relative turning between said tractor and trailer said plate member has pivotal action relative to said trailer at all times about the axis of said one of said pins while the same moves along its rectilinear path.

5. In combination with a tractor having a fifth Wheel member thereon and a trailer having one end supported thereby, of a coupling device comprising, a movable member carried by said trailer, a pivot pin and a follower pin on said movable member, iirst guide means on said trailer and arranged to guide said pivot pin for rectilinear movement longitudinally of said trailer, second guide means on said trailer and arranged to guide said follower pin for movement transversely of said trailer, at least the intermediate portion of said transverse movement being rectilinear, and means connecting said movable member and said iiith wheel member together to prevent relative movement therebetween, both said guide means being arranged so that during relative turning between said tractor and trailer said movable member has pivotal action relative to said trailer all time about the axis of said pivot pin while the same moves along its rectilinear path whereby a close coupling is provided and turning clearance of progressively increasing amount is provided as said tractor is turned out of alignment with said trailer.

6. In combination with a tractor having a fifth wheel member thereon and a trailer having one end supported thereby, of a coupling device comprising, a plate Jfixed to said trailer and having therein a rectilinear slot extending longitudinally of said trailer and a transverse slot arranged in front of said longitudinal slot and extending transversely of said trailer, said transverse slot having at least its central portion rectilinear, a movable member carried by said trailer, an upstanding pivot pin on said movable member and guided for movement along said longitudinal slot, an opstanding follower pin on said movable member and guided for movement along said transverse slot, and means separably connecting said movable member and said fifth wheel member together to prevent relative movement therebetween, both said slots being arranged so that during relative turning between said tractor and trailer said movable member has pivotal action relative to said trailer at all times about the axis of said pivot pin while the same moves rectilinearly along said longitudinal slot whereby a close coupling is provided and turning clearance or progressively increasing amount is provided as said tractor is turned out of alignment with said trailer.

'7. In combination with a tractor having a liith wheel member thereon and a trailer having one end supported thereby, ci a coupling device comprising, a plate ixed to said trailer and having therein a rectilinear slot extending longitudinally of said trailer and a transverse slot arranged in front of said longitudinal slot and extending transversely of said trailer, said transverse slot having at least its central portion rectilinear, a movable member carried by said trailer, an upstanding pivot pin on said movable member and guided for movement along said longitudinal slot, an upstanding follower' pin on said movable member and guided for movement along said transverse slot, a depending king pin on said movable member removably locked to said fifth wheel member, and means on said movable member engageable with said fth wheel member to prevent relative rotation between said members about the axis of said king pin, both said slots being arranged so that during relative turning between said tractor and trailer said movable member has pivotal action relative to said trailer at all times about the axis or" said pivot pin while the same moves rectilinearly along said longitudinal slot whereby a close coupling is provided and turning clearance of progressively increasing amount is provided as said tractor is turned out of alignment with said trailer.

S. In combination with a tractor having a fifth wheel member thereon and a trailer having one end supported thereby, of a coupling device cornprising, a plate fixed to Said trailer and having therein a longitudinal slot and a transverse slot arranged in front of said longitudinal slot, said transverse slot having at least its central portion rectilinear, a movable member carried by said trailer, an upstanding pivot pin on said movable member and guided in said longitudinal slot for rectilinear movement, an upstanding follower pin on said movable member and guided in said transverse slot, a depending king pin on said movable member removably locked to said fifth wheel member and arranged intermediate said pivot and follower pins and in line therewith, and transversely spaced abutments on said movable member in rear of said king pin and engaging the sides of said iifth wheel member to prevent relative rotation between said members about the axis of said king pin, whereby a close coupling is provided and turning clearance is permitted when said tractor is turned out of alignment with said trailer.

9. In combination with a tractor having a ith wheel member thereon and a trailer having one end supported thereby, of a coupling device comprising, a plate xed to said trailer and having therein a longitudinal slot and a transverse slot arranged in front or said longitudinal slot, said transverse slot having at least its central l portion rectilinear, a movable member carried by said trailer, an upstanding pivot pin on said movable member and guided in said longitudinal slot for rectilinear movement, an opstanding follower pin on said movable member and guided in said transverse slot, a depending king pin on said movable member removably locked to said fifth wheel member and arranged intermediate said pivot and follower pins and in line therewith, and depending guide bars on said movable member and arranged in rear of said king pin on opposite sides of the line connecting the centers of said pivot and follower pins and engaging the sides of said fifth wheel member to maintain the said ins in line with the center line of said tractor at all times, whereby a close coupling is provided and turning clearance is permitted when said tractor is turned out of alignment with said trailer.

10. In combination with a tractor having a fth wheel member thereon and a trailer having a deck plate xed thereto and overlapping said fth wheel member, of a coupling device comprising, a plate member arranged between said fifth wheel member and said deck plate and carried by and movable relative to said deck plate, a pair of permanently spaced upstanding pins fixed to said plate member, spaced guide Walls on opposite sides of a slot in said deck plate which extends longitudinally of said trailer and which receives one of said pins, spaced guide walls on opposite sides of a slot in said deck plate which is arranged in front of said longitudinal slot and extends transversely of said trailer and which receives the other of said pins, the opposing faces of said last mentioned guide Walls extending rectilinearly at least along the central portion of said transverse slot, inwardly projecting and opposing flanges at the base of each of the corresponding pairs cf said guide Walls, a roller sleeve on each of said pins 2 engageable with the corresponding pair of said guide Walls vand having its lower end opposing the corresponding ones of said flanges, a Washer on the upper end of each of said pins and straddling the corresponding pair of said guide Walls, a nut on each of said pins above the corresponding one of said Washers, said plate member having pivotal action relative to said trailer at all times about the axis of said one of said pins, and means connecting said plate member to said fth wheel member with the line connecting the centers of said pins in line with the centerline of said tractor and maintaining such arrangement at all times, whereby a close coupling is provided and turning clearance is permitted when said tractor is turned out of alignment with said trailer.

Name Date Edwards Oct. 6, 1936 Number 

